Antonio, you may find this interesting the schedule of Amby Burfoot back in the 1960's when many runners were finding success with LSD (long slow distance).
Just because something don't make sense to the scientist don't mean it doesn't work. We need the psychologist involved in these conversations.
From Joe Henderson's book published by T&FN 1970.
Ambrose Joel Burfoot. 6'0'', 140 lbs. Born Aug. 19, 1946. Began racing at age 17. "Serious competition will probably cease for me before jogging does. I believe I will continue running or a very long time." Self coached influenced by John Kelly.
Best Times: 440 yds-57.9; 880yds.-202.5; mile-4:19; 2mile-8:45.6; 3miles-13:44.8; 6miles-29:26; Marathon-2:14:28.8 Favorite race, marathon.
Training: (1968 season) twice a day (6:30 a.m., 3p.m.) 7 days a week 12 months a year. About 115 miles per week. longest ever training run: 38 miles.
Description: "Under ideal conditions of good health, sufficient time (both for necessary training and the even more ecessary relaxation) and proper motivation, I would train as follows:
Mon.-Sat. 10miles a.m. 15miles p.m.; Sun. 25 miles.
I accomplished this schedule during the first two weks of February 1968. All running was at approximately 7:00 pace. Without any speedwork at all, I then went onto the track (indoors) and ran 8:45, which is still far nd away my most startling running performance. I ran with an ease which absolutely amazed me. I then began thinking about more track meets and adding a little speed, and got slower every week. By mid March I was a consistent 9:02 2 miler.
I spent the fall of 68 training 5 or 6 times per week. My weekday runs were 15 milers, while on the weekend I got out for longer runs including a 38 and a 36. I averaged 85 over this period and only topped 100 once. Yet, I felt very good and began doing "Oslerian pickups" (gradual accelerations). On my 15 I would run easily for 2 miles, do 7x800m pickups in the next 10-11 miles, and then do hard, short pickups for the last two miles. (This is the training that led to his 2:14 race in Japan which was within 1 sec. of the then AR. held by B. Edelen.